Pen has been used by human being for writing purposes for a long time. After a long time writing, a user feels sore or uncomfortable at his/her finger tips and a part of his/her hand between the thumb and index finger thereof because of the long time rubs between the pen and the finger tips and the pen between the part of his/her hand between the thumb and index finger thereof.
A conventional pen holding auxiliary device is made of one piece flexible material such as rubber or silica gel. The device has an elongated configuration having a channel therethrough. The device is placed to embrace the shaft of a pen. The device has a first portion for being placed between finger tips such as finger tips of thumb, index finger and middle finger and a second portion for being placed against a part of a user's hand between his/her thumb and index finger. Therefore the device provides comfortable touches between the pen and the hand thereby the user can continue a long time writing. However, the distance between the first portion and the second portion is constant. Accordingly the device cannot fit users' hands of different sizes. The second portion of the device is not in the proper position to provide cushion effect to the part of his/her hand between the thumb and the index finger when the user has bigger or smaller hands. For instances, a pen holding auxiliary device for children doesn't fit the same purpose for adults. It's not economic and practical to produce pen holding auxiliary devices with different lengths. Accordingly, it would be very desirable to have a pen holding auxiliary device not only providing comfortable touches but also the length thereof is adjustable to fit users' hands of different sizes.